JP2007003671A - Liquid crystal device, method for manufacturing liquid crystal device, and electronic appliance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal device for which moisture absorption and moisture intrusion are prevented. <P>SOLUTION: The liquid crystal device 100 is constructed with a pair of substrates 10, 20 placed opposite to each other and having a liquid crystal 50 interposed in between. Alignment layers 40 (60) are arranged on respective inside faces of the pair of substrates 10, 20. A sealing material 52 is arranged between the alignment layers 40, 60 in the state of enclosing the liquid crystal 50 in between. A moisture resistant film 90 is formed on the side end face side of the pair of substrates 10, 20 by applying a sol-gel solution containing a silane coupling agent, a metal alkoxide, and water thereto in a state of covering at least the sealing material 52 and the alignment layers 40, 60 and hardening it. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a liquid crystal device, a method for manufacturing a liquid crystal device, and an electronic apparatus.

  A liquid crystal device used as a light modulation means mounted on a liquid crystal projector or the like or a direct-view display device mounted on a mobile phone or the like mainly includes a pair of substrates having electrodes for applying a voltage to a liquid crystal layer. Has been. A conductive film (pixel electrode, counter electrode, etc.) and an alignment film for controlling the initial alignment state of liquid crystal molecules are formed on each inner surface side of the pair of substrates constituting the liquid crystal device. The alignment films are bonded to each other by a sealing material so that the substrates are bonded to each other, and liquid crystal is sealed in a region surrounded by the sealing material.

By the way, in the liquid crystal device, moisture absorption and moisture intrusion cause deterioration in quality, and therefore, a technique for performing water repellency treatment on the surface of the alignment film or forming a film having water repellency on the surface of the alignment film is provided. ing.
JP 2002-202509 A

  However, in the technique of forming a water repellent film on the surface of the alignment film, the pretilt of the liquid crystal element is disturbed due to the non-uniform thickness of the water repellent film, or bubbles are generated in the liquid crystal layer due to contact with the water repellent film. May cause problems such as the occurrence of In addition, the water repellency of the alignment film may decrease due to light or heat used to cure the sealing material for bonding the pair of substrates.

  Furthermore, even if the surface of the alignment film is subjected to water repellency treatment in this way, moisture permeation occurs from the interface between the alignment film and the sealing material or from the side surface of the sealing material itself, and moisture penetrates into the liquid crystal device. Quality degradation will occur.

  SUMMARY An advantage of some aspects of the invention is that it provides a liquid crystal device capable of preventing moisture absorption and moisture intrusion, a method for manufacturing the same, and an electronic apparatus using the liquid crystal device.

In order to achieve the above object, a liquid crystal device of the present invention is a liquid crystal device in which liquid crystal is sandwiched between a pair of substrates facing each other,
An alignment film is provided on each inner surface of the pair of substrates,
A sealing material is provided between the alignment films in a state where the liquid crystal is sealed,
A sol-gel solution containing a silane coupling material, a metal alkoxide, and water is applied and cured on the side end surfaces of the pair of substrates in a state of covering at least the sealing material and the alignment film. It is characterized in that a moisture-proof film is formed.

  According to this liquid crystal device, a sol-gel solution containing a silane coupling material, a metal alkoxide, and water is at a position that covers at least the sealing material and the alignment film on the side end surfaces of the pair of substrates. Since the moisture-proof film is formed, the moisture-proof film prevents moisture permeation from the interface between the alignment film and the sealing material and from the side surface of the sealing material itself, thereby reducing the quality of the liquid crystal device due to moisture absorption (moisture permeability). Is prevented.

In the liquid crystal device, the metal alkoxide is preferably composed of at least one of Zr alkoxide, Al alkoxide, Ti alkoxide, and Mg alkoxide.
In this way, Zr, Al, Ti, and Mg in these metal alkoxides become, for example, oxides, which are combined with the polysiloxane skeleton formed by the silane coupling material, or organic functionalities in the alignment film and the sealing material. Since it bonds to a group or the like, the film density of the resulting moisture barrier film is increased, moisture permeability is decreased, and moisture resistance is increased. Moreover, since the adhesiveness with the sealing material and the alignment film is increased, the moisture-proof effect is ensured over a long period of time, and the reliability is improved. Further, it also has an antistatic function by discharging charges accumulated in the alignment film or the like.

In the liquid crystal device, the silane coupling material preferably includes a plurality of types of alkoxysilanes, and these alkoxysilanes preferably have different numbers of carbon atoms in the respective alkoxy groups.
Thus, if the number of carbons in each alkoxy group of a plurality of types of alkoxysilanes is different from each other, particularly when these are composed of a long chain with a large number of carbons and a short chain with a small number of carbons, When the short chain enters the structure, the film density of the moisture-proof film becomes higher, the moisture permeability becomes lower, and the moisture resistance becomes higher.

In the liquid crystal device, the sol-gel solution contains a water-repellent material having a water-repellent group, and the moisture-proof film obtained by curing the sol-gel solution has water repellency. Is preferred.
In this way, the water repellency of the moisture-proof film prevents moisture from adhering to the moisture-proof film, that is, the sealing material and the alignment film. Is prevented. In addition, it is of course possible to prevent moisture from entering the liquid crystal device due to moisture adhesion.

In this liquid crystal device, it is preferable that the moisture-proof film is formed on the entire surface on the side end surfaces of the pair of substrates.
In this way, moisture is prevented from adhering to the entire surface on the side end surfaces of the pair of substrates, so that moisture permeation easily occurs from the side end surfaces of the pair of substrates. It is prevented. Further, the moisture permeation itself is prevented more favorably because the moisture-proof film is formed on the entire side end surface.

The method for producing a liquid crystal device of the present invention includes a step of bonding a pair of substrates having an alignment film formed on the inner surface through a sealing material;
Disposing a liquid crystal in a region surrounded by the sealing material;
Applying a sol-gel solution containing a silane coupling material, a metal alkoxide, and water in a state of covering at least the sealing material and the alignment film on the side end face sides of the pair of substrates;
And a step of curing the sol-gel solution to form a moisture-proof film.

  According to this method of manufacturing a liquid crystal device, at least the sealing material and the alignment film on the side end face sides of the pair of substrates are covered with a sol-gel solution containing a silane coupling material, a metal alkoxide, and water. The moisture-proof film is formed at the position where the moisture-proof film prevents moisture permeation from the interface between the alignment film and the sealing material and from the side surface of the sealing material itself, thereby improving the quality of the liquid crystal device due to moisture absorption (moisture permeability). A decrease can be prevented.

An electronic apparatus according to the present invention includes the above-described liquid crystal device.
According to this electronic device, since the liquid crystal device in which deterioration due to moisture absorption (moisture permeability) is prevented is provided, the electronic device itself is also prevented from being deteriorated in quality and improved in display reliability. .

(Liquid crystal device)
FIG. 1 is a schematic cross-sectional view showing a liquid crystal cell as an embodiment of the liquid crystal device of the present invention.
As shown in FIG. 1, the liquid crystal cell 100 has a configuration in which a liquid crystal 50 (liquid crystal layer) is sandwiched between a pair of substrates 10 and 20 facing each other. A translucent conductive film 9 (pixel electrode) and an alignment film 40 are sequentially disposed on the inner surface side (opposing surface side) of the substrate 10. On the other hand, a translucent conductive film 21 (common electrode, counter electrode) and an alignment film 60 are sequentially formed on the inner surface side (opposing surface side) of the substrate 20.

  The substrate 10 and the substrate 20 are bonded together by a sealing material 52 between the alignment films 40 and 60, and the liquid crystal 50 is sealed and held in a region partitioned by the sealing material 52. In the sealing material 52, for example, a liquid crystal injection port (not shown) for injecting liquid crystal after the substrate 10 and the substrate 20 are bonded together is formed. However, before the substrate 10 and the substrate 20 are bonded together, a sealing material 52 is applied in an annular shape in advance without forming a liquid crystal injection port on one substrate, and the liquid crystal is filled inside the sealing material 52. The substrate 10 and the substrate 20 may be bonded together. In that case, the liquid crystal injection port is not formed in the sealing material 52 as described above.

  As the conductive films 9 and 21, for example, an indium oxide film doped with tin (ITO film) is used. In addition, various known conductive films having translucency and conductivity, such as an IZO film and an FTO film, can also be used. In the case where translucency is not required, various known conductive films having excellent conductivity can be applied. The ITO film can be formed by an evaporation method, a sputtering method, a baking method (also referred to as a coating pyrolysis method), or the like.

  In order to form an ITO film by using the sputtering method, an ITO transparent conductive film made of indium oxide and tin oxide is set to a predetermined film thickness (for example, 0.8 mm) by setting the substrate surface temperature to a predetermined temperature (for example, 200 ° C.). A film is formed to a thickness of 05 μm to 10 μm, and heat treatment is performed while maintaining a predetermined temperature (for example, 200 ° C. to 250 ° C.) for a certain time (for example, 60 minutes). Thereafter, patterning is performed in a desired planar shape by photolithography as necessary.

  In order to form the ITO film using the firing method, a liquid material of the ITO film is placed on the substrate, and the film is heat-treated. Formation of a conductive film using a liquid phase method is advantageous in reducing manufacturing costs. As an arrangement technique of the liquid material, an inkjet method, a Cap coating method, a spin coating method, or the like can be used. By using an organic solvent in which an organic compound of indium and an organic compound of tin are dissolved in the presence of an organic amine as the liquid material, firing at a relatively low temperature (for example, 250 ° C. or less) becomes possible. Further, after a fine particle film containing light-transmitting conductive fine particles is formed on a substrate, an organic solvent in which the light-transmitting conductive fine particles are dissolved is infiltrated into the fine particle film, and then the film is subjected to heat treatment (firing). ), A light-transmitting conductive film having excellent conductivity can be obtained even when the firing temperature is relatively low (for example, 250 ° C. or lower).

As the alignment films 40 and 60, either an organic alignment film or an inorganic alignment film can be applied.
The organic alignment film can be formed, for example, by performing an alignment process such as rubbing on the surface of a polymer film such as polyimide. An inorganic alignment film has higher light resistance and heat resistance than an organic alignment film. After an inorganic film such as SiO ₂ is formed by vapor deposition or sputtering, the surface of the inorganic film is irradiated with an ion beam or particle beam. It can be formed by performing an orientation treatment. Alternatively, the inorganic alignment film can be formed by a so-called oblique vapor deposition method in which an inorganic material is incident on the substrate obliquely to form a film having an oblique columnar structure.

  Here, a moisture-proof film 90 is formed on the side surface of the liquid crystal cell 100 of the present embodiment. The moisture-proof film 90 continuously covers the entire surface on the side end face side of the substrates 10, 20, that is, the side surfaces (end faces) of the substrates 10, 20, the conductive films 9, 21, the alignment films 40, 60, and the sealing material 52. And it is arrange | positioned so that it may cover over a perimeter. In addition, the moisture-proof film 90 has a particularly low moisture permeability, and thus has a function of satisfactorily preventing moisture permeability at a portion covered by the moisture-proof film 90.

  That is, the moisture-proof film 90 is formed by applying and curing a sol-gel solution containing a silane coupling material, a metal alkoxide, and water. As the silane coupling material, one or more selected from various alkoxysilanes and acryloxysilanes are used. Specifically, tetramethoxysilane, 3-glycidoxyproyl-trimethoxysilane, 3-aminopropyl-triethoxysilane, N-trimethoxysilylpropyl-N N, N-trimethylammonium chloride, methacryloxypropyltrimethoxysilane, etc. are preferably used. Here, in particular, when a plurality of types of silane coupling materials, for example, a plurality of types of alkoxysilanes are used, it is preferable to use those alkoxysilanes having different numbers of carbon atoms in the respective alkoxy groups. That is, an alkoxysilane having an alkoxy group (alkyl group) having a long straight chain and a long chain, and an alkoxy group (alkyl group) having a short straight chain and a short chain. It is preferable to use a mixture of alkoxysilane having If such a plurality of types of alkoxysilanes are used, the short chain enters the network structure of long chains as will be described later, thereby increasing the film density of the resulting moisture-proof film 90 and reducing its moisture permeability. The moisture resistance of the moisture barrier film 90 can be further increased.

  Moreover, as a metal alkoxide, Zr alkoxide, Al alkoxide, Ti alkoxide, and Mg alkoxide are suitable, and the 1 type or multiple types selected from these are used suitably. Specifically, aluminum-sec-butoxide, zirconium-n-propoxide, and the like are preferable. The sol-gel solution in the present invention is added to the mixture of the silane coupling material and the metal alkoxide by adding water necessary to hydrolyze them and performing appropriate treatment such as stirring at an appropriate temperature. It is said.

In the present embodiment, the moisture-proof film 90 has water repellency. This is because the sol-gel solution is formed to contain a water-repellent material having a water-repellent group, so that the moisture-proof film 90 obtained by curing the sol-gel solution has water repellency. -ing
Here, the water repellent material may be newly added to these materials as materials other than the silane coupling material and metal alkoxide, or the silane coupling material or metal alkoxide itself may be added. Alternatively, a water repellent material may be used. That is, a water-repellent material may be added to the silane coupling material and metal alkoxide to form a sol-gel solution, or a silane coupling material or metal alkoxide having water repellency may be used. A sol-gel solution may be formed.

  When a water repellent material is newly added as a material other than the silane coupling material and the metal alkoxide, for example, an organic thin film made of an organic molecule such as a silane compound or a surfactant is applied to the surface to be treated. Those which are formed and impart water repellency are used. Organic molecules for making the treated surface water repellent modify the surface properties of the substrate on the opposite side to the functional group that can be physically or chemically bonded to the substrate that forms the treated surface. And a functional group that makes liquid repellency (controlling the surface energy), bonds to a base material to form an organic thin film, and ideally becomes a monomolecular film. In particular, organic molecules in which the organic structure that connects the functional group that can bind to the base material and the functional group on the opposite side of the functional group is a linear or partially branched carbon chain of carbon binds to the base material and self-assembles. This is preferable.

As such a self-organizing compound, that is, the water repellent material, for example, a silane compound represented by the following general formula (1) can be used. In formula (1), R ¹ represents an organic group, X ¹ and X ² represent —OR ² (alkoxy group), —R ² (alkyl group), —Cl (chlorine group), and X ¹ and X ² R ² contained in 1 represents an alkyl group having 1 to 4 carbon atoms, and a represents an integer of 1 to 3.
R ¹ SiX ¹ _a X ² _(3-a) (1)

  In the silane compound represented by the general formula (1), an organic group is substituted on the silane molecule, and an alkoxy group, an alkyl group, or a chlorine group is substituted on the remaining bonding group. In particular, the silane compound having an alkoxy group is an alkoxy silane serving as the silane coupling material constituting the sol-gel solution in the present invention, and therefore, as described above, when it is desired to impart water repellency to the silane coupling material. In this case, an alkoxysilane represented by the general formula (1) may be used.

Examples of the organic group R ¹ include, for example, phenyl group, benzyl group, phenethyl group, hydroxyphenyl group, chlorophenyl group, aminophenyl group, naphthyl group, anthrenyl group, pyrenyl group, thienyl group, pyrrolyl group, cyclohexyl group, cyclohexane Hexenyl, cyclopentyl, cyclopentenyl, pyridinyl, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, octadecyl, n- Octyl group, chloromethyl group, methoxyethyl group, hydroxyethyl group, aminoethyl group, cyano group, mercaptopropyl group, vinyl group, allyl group, acryloxyethyl group, methacryloxyethyl group, glycidoxypropyl group, acetoxy group Etc. can be illustrated.
The alkoxy group and chlorine group of X ¹ and X ² are functional groups for forming a Si—O—Si bond and the like, and are hydrolyzed by water and eliminated as alcohol or acid. Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, a sec-butoxy group, and a tert-butoxy group.
The number of carbon atoms of R ² is in the range of 1 to 4 from the viewpoint that the molecular weight of the alcohol to be eliminated is relatively small, can be easily removed, and the deterioration of the denseness of the formed film (moisture-proof film 90) can be suppressed. It is preferable.

A typical water-repellent silane compound represented by the general formula (1) includes a fluorine-containing alkylsilane compound. In particular, R ¹ has a structure represented by the perfluoroalkyl structure C _n F _{(2n + 1)} , and examples thereof include compounds represented by the general formula (2). In the formula (2), n represents an integer of 1 to 18, m represents an integer of 2 to 6, and X ^1, X ² and a represent the same meaning as in the formula (1).
By using the fluorine-containing alkylsilane compound, each compound is oriented so that the fluoroalkyl group is located on the surface of the resulting moisture-proof film 90 and a self-assembled film is formed. Can be granted.
_{C n F (2n + 1)} (CH 2) m SiX 1 a X 2 (3-a) ... (2)

More specifically, CF ₃ —CH ₂ CH ₂ —Si (OCH ₃ ) ₃ , CF ₃ (CF ₂ ) ₃ —CH ₂ CH ₂ —Si (OCH ₃ ) ₃ , CF ₃ (CF ₂ ) ₅ —CH ₂ CH ₂ —Si (OCH ₃ ) ₃ , CF ₃ (CF ₂ ) ₅ —CH ₂ CH ₂ —Si (OC ₂ H ₅ ) ₃ , CF ₃ (CF ₂ ) ₇ —CH ₂ CH ₂ —Si (OCH ₃₎ ) ₃ , CF ₃ (CF ₂ ) ₁₁ —CH ₂ CH ₂ —Si (OC ₂ H ₅ ) ₃ , CF ₃ (CF ₂ ) ₃ —CH ₂ CH ₂ —Si (CH ₃ ) (OCH ₃ ) ₂ , CF _{3 (CF 2) 7 -CH 2} CH 2 -Si (CH 3) (OCH 3) 2, CF 3 (CF 2) 8 -CH 2 CH 2 -Si (CH 3) (OC 2 H 5) 2, CF ₃ (CF ₂ ) ₈ —CH ₂ CH ₂ —Si (C ₂ H ₅ ) (OC ₂ H ₅ ) _{2 and the} like.

Further, ^{R 1} Gapa - perfluoroalkyl ether structure _{C n F (2n + 1)} O p F can also be mentioned those having a structure represented by 2p _{O r.} Specific examples thereof include a compound represented by the following general formula (3).
_{C p F (2p + 1)} O (C p F 2p O) r (CH 2) m SiX 1 a X 2 (3-a) ... (3)

In Formula (3), m represents an integer of 2 to 6, p represents an integer of 1 to 4, r represents an integer of 1 to 10, and X1, X2, and a represent the same meaning as described above.
Specific examples of the compound include CF ₃ O (CF ₂ O) ₆ —CH ₂ CH ₂ —Si (OC ₂ H ₅ ) ₃ , CF ₃ O (C ₃ F ₆ O) ₄ —CH ₂ CH ₂ —. _{Si (OCH 3) 3, CF} 3 O (C 3 F 6 O) 2 (CF 2 O) 3 -CH 2 CH 2 -Si (OCH 3) 3, CF 3 O (C 3 F 6 O) 8 -CH ₂ CH ₂ —Si (OCH ₃ ) ₃ , CF ₃ O (C ₄ F ₉ O) ₅ —CH ₂ CH ₂ —Si (OCH ₃ ) ₃ , CF ₃ O (C ₄ F ₉ O) ₅ —CH ₂ CH _{2 -Si (CH 3) (OC} 2 H 5) 2, CF 3 O (C 3 F 6 O) 4 -CH 2 CH 2 -Si (C 2 H 5) (OCH 3) 2 , and the like.

  Silane compounds having a fluoroalkyl group or a perfluoroalkyl ether structure are collectively referred to as “FAS”. These compounds may be used alone or in combination of two or more. In addition, by using FAS, adhesiveness with a base material and favorable water repellency can be obtained.

Further, as the water repellent material, a surfactant represented by the following general formula (4) can also be used. In Formula (4), R ¹ represents a hydrophobic organic group, Y ¹ represents a hydrophilic polar group, —OH, — (CH ₂ CH ₂ O) _n H, —COOH, —COOA, —CONH ₂ , —SO ₃ H, —SO ₃ A, —OSO ₃ H, —OSO ₃ A, —PO ₃ H ₂ , —PO ₃ A, —NO ₂ , —NH ₂ , —NH ₃ B (ammonium salt), ≡NHB (Pyridinium salt), -NX13B (alkyl ammonium salt) and the like. However, A represents one or more cations, and B represents one or more anions. X1 represents the same alkyl group having 1 to 4 carbon atoms as described above.
R ¹ Y ¹ (4)

The surfactant represented by the general formula (4) is a compound in which a hydrophilic functional group is bonded to a lipophilic organic group R ¹ . Y ¹ represents a hydrophilic polar group, which is a functional group for bonding or adsorbing to the base material, and the organic group R ¹ has lipophilicity and is arranged on the opposite side of the hydrophilic surface so as to be on the hydrophilic surface. A lipophilic surface is formed. Examples of the organic group R ¹ include, for example, phenyl group, benzyl group, phenethyl group, hydroxyphenyl group, chlorophenyl group, aminophenyl group, naphthyl group, anthrenyl group, pyrenyl group, thienyl group, pyrrolyl group, cyclohexyl group, cyclohexane Hexenyl, cyclopentyl, cyclopentenyl, pyridinyl, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, octadecyl, n- Octyl group, chloromethyl group, methoxyethyl group, hydroxyethyl group, aminoethyl group, cyano group, mercaptopropyl group, vinyl group, allyl group, acryloxyethyl group, methacryloxyethyl group, glycidoxypropyl group, acetoxy group Etc. can be illustrated.

A typical water-repellent surfactant represented by the general formula (4) includes a compound having a fluorine-containing alkyl structure. In particular, those having a structure in which R ¹ is represented by the perfluoroalkyl structure C _n F _{(2n + 1)} are useful. More _{specifically, F (CF 2 CF 2)} (1~7) -CH 2 CH 2 -N + (CH 3) 3 Cl -, C 8 F 17 SO 2 NHC 3 H 6 -N + (CH 3 ), F (CF ₂ CF ₂ ) _(1-7) —CH ₂ CH ₂ SCH ₂ CH ₂ —CO ₂ —Li ⁺ , C ₈ F ₁₇ SO ₂ N (C ₂ H ₅ ) —CO ₂ —K ⁺ , _{(F (CF 2 CF 2)} (1~7)) CH 2 CH 2 O) 1,2 PO (O - NH 4 +) 1,2, C 10 F 21 SO 3 - NH 4 +, C 6 F 13 _{CH 2 CH 2 SO 3 H,} C 6 F 13 CH 2 CH 2 SO 3 - NH 4 +, C 8 F 17 SO 2 N (C 2 H 5) - (CH 2 CH 2 O) (0~25) H _{, C 8 F 17 SO 2 N} (C 2 H 5) - (CH 2 CH 2 O) (0~25) CH _{, F (CF 2 CF 2)} (1~7) -CH 2 CH 2 O- (CH 2 CH 2 O) (0~25) H and the like.

The surfactant having a fluoroalkyl group may be used alone or in combination of two or more. In addition, adhesiveness with a base material and favorable water repellency can be obtained by using the surfactant which has a fluoroalkyl group.
Further, it may have a structure having an alkyl group that does not contain fluorine, and water repellency can be obtained by forming a dense film on a general surfactant.

Further, when the silane coupling material or the metal alkoxide itself is used as a water repellent material, the silane coupling material or metal alkoxide having such a water repellency is, for example, as described above, an alkoxy compound as a silane coupling material. Silane may be used. In order to further improve the water repellency, a fluorine group introduced into the alkoxy group of this alkoxysilane or the alkoxy group of the metal alkoxide, for example, a perfluoroalkyl structure [C _n F _{(2n + 1)} ] May be used. Furthermore, even if a fluorine group is not introduced, the moisture-proof film 90 obtained by forming a hydrophobic group if the alkyl group in the alkoxy group has a large number of carbon atoms and the straight chain is sufficiently long. Has water repellency.

  A sol-gel solution formed by such a material, that is, a sol-gel solution formed by adding water to a mixture of a silane coupling material and a metal alkoxide and a water-repellent material added as necessary, It is formed on the moisture-proof film 90 by being applied to the side end surfaces of the substrates 10 and 20 and further subjected to a curing process. Here, in the present embodiment, as the sol-gel solution, the tetramethoxysilane, 3-glycidoxyproyl-trimethoxysilane, 3-aminopropyl-triethoxysilane, aluminum-sec-butoxide, and zirconium-n-propoxide are mixed at an appropriate ratio, and these are mixed. By adding an equivalent amount of water to the mixture and stirring, a sol-gel solution having high viscosity and thus high tackiness is prepared.

  The application of the sol-gel solution thus obtained is not particularly limited, and various methods can be adopted. Specifically, a dipping method (dip coating method), a spray coating method, various printing methods, a dispensing method, an inkjet method, and the like are preferably used. In the present embodiment, since the moisture-proof film 90 is formed on the entire surface on the side end surfaces of the substrates 10 and 20, for example, the outer surfaces (front surfaces) of the substrates 10 and 20 that are the front and back surfaces of the liquid crystal cell 100 are masked. In this state, a method of immersing the side end surfaces of the substrates 10 and 20 in the sol-gel solution is preferably employed because it is simple.

When applied in this manner, the sol-gel solution adheres well to the application site because of its high adhesiveness as described above. Therefore, the sol-gel solution is cured by irradiating the coated surface with ultraviolet rays for several seconds to 60 seconds, for example, and the moisture-proof film 90 can be obtained. Alternatively, the moisture-proof film 90 is obtained by curing the sol-gel solution by performing heat treatment at a temperature of 150 ° C. or less (for example, 80 ° C. to 150 ° C.) at a temperature that does not deteriorate the characteristics of the liquid crystal cell 100 for several minutes to several tens of minutes. You can also. Of course, the curing time can be further shortened by using such ultraviolet irradiation treatment and heat treatment in combination.
Prior to the formation of such a moisture-proof film 90, it is desirable to wash the application portion of the sol-gel solution by an appropriate method.

The moisture-proof film 90 obtained in this manner has a remarkably low value of about 0.16 g / m ² · 24 hr while the moisture permeability of the sealing material 52 is about 5 g / m ² · 24 hr, for example. In particular, moisture permeation from the interface between the alignment films 40 and 60 and the sealing material 52 and the side surface of the sealing material 52 itself can be prevented more favorably.
Therefore, in the liquid crystal cell 100 of the present embodiment, quality deterioration due to moisture absorption (moisture permeability) is reliably prevented.

In addition, since Zr alkoxide and Al alkoxide are used as the metal alkoxide for the sol-gel solution forming the moisture-proof film 90, these metal alkoxides are hydrolyzed and the metal (Zr, Al) is, for example, [ZrO ₆ ] or [AlO ₆ ], which is an oxide that forms an octahedral structure, such as when bonded to a structure made of an organic functional device or a silane coupling material at the application site, the film density of the moisture-proof film 90 obtained in particular. Becomes higher, moisture permeability becomes lower and moisture resistance becomes higher. That is, if only the silane coupling agent, which is hydrolysed becomes tetrahedral structure as [SiO _4], which is the only bind to the organic functional device, etc. of the coating portion. However, a film having two types of structures including the octahedron structure as described above has a higher film density and a lower moisture permeability than a film having one type of structure. The nature becomes higher. In addition, even in the state of the sol-gel solution before curing, the viscosity of the liquid becomes high and the adhesiveness becomes high by increasing the density of the liquid, thereby improving the adhesion to the application site.

Further, since the metal (Zr, Al) in the metal alkoxide is present in the moisture-proof film 90, the anti-static function is exhibited by releasing the charge accumulated in the alignment films 40, 60 and the like. .
If a polar compound such as N-trimethoxysilylpropyl-N, N, N-trimethylammonium chloride is used as the silane coupling material, for example, this has a function of releasing charges accumulated in the alignment films 40, 60, etc. As a result, the moisture-proof film 90 exhibits an antistatic function.

  In addition, as a silane coupling material for forming a sol-gel solution, an alkoxysilane having an alkoxy group (alkyl group) having a large number of straight-chain carbons and a long straight chain, and a straight chain having a small number of straight-chain carbons. If an alkoxysilane having an alkoxy group (alkyl group) having a short chain is mixed and used, the short chain enters the network structure of the long chain, and the film density of the moisture-proof film 90 becomes higher. Moisture permeability becomes lower and moisture resistance becomes higher.

  Further, since the moisture-proof film 90 has water repellency, and thus prevents moisture from adhering to the moisture-proof film 90, for example, moisture adheres to the sealing material 52 and the alignment films 40 and 60. Thus, moisture permeation can be prevented from being easily caused by adhesion of moisture. In addition, it is possible to prevent moisture from entering the liquid crystal cell 100 due to moisture adhesion. In particular, since the moisture-proof film 90 is formed on the entire surface of the side end surfaces of the substrates 10 and 20, moisture permeation and water intrusion from the side end surfaces of the substrates 10 and 20 can be prevented better.

  Furthermore, according to the liquid crystal cell 100, it is possible to omit the water repellent treatment on the surfaces of the alignment films 40 and 60, and the influence on the liquid crystal element caused by forming the water repellent film on the surfaces of the alignment films 40 and 60. (For example, pretilt disturbance due to non-uniformity of the water repellent film, generation of bubbles in the liquid crystal layer 50 due to contact with the water repellent film, etc.) can be avoided. In addition, since the moisture-proof film 90 is formed after the pair of substrates 10 and 20 are bonded together, it is possible to avoid the function of the moisture-proof film 90 from being deteriorated by light or heat when the sealing material 52 is cured.

Next, a modification of the embodiment shown in FIG. 1 will be described with reference to FIG. 2, FIG. 3, and FIG.
The liquid crystal device (liquid crystal panel 130) of FIG. 2 differs from FIG. 1 in that polarizing plates 45 and 65 and dustproof plates 46 and 66 are disposed on the outer surface side of the substrates 10 and 20, and the polarizing plates 45, A moisture-proof film 90 is formed to further cover the side surfaces of 65 and the side surfaces of the dust-proof plates 46 and 66. That is, the moisture-proof film 90 is applied to the entire surface on the side end face side of the substrates 10 and 20, that is, the side surfaces of the substrates 10 and 20, the conductive films 9 and 21, the alignment films 40 and 60, and the sealing material 52. , 65 and the dustproof plates 46, 66 are disposed so as to cover the entire circumference continuously. Also in the liquid crystal panel 130 of the present example, the joint portion between the substrates 10 and 20 and the conductive films 9 and 21, the joint portion between the conductive films 9 and 21 and the alignment films 40 and 60, and the alignment films 40 and 60 and the sealing material. In addition to the bonding portion with 52, the bonding portions between the substrates 10 and 20 and the polarizing plates 45 and 65 and the bonding portions between the polarizing plates 45 and 65 and the dustproof plates 46 and 66 are covered with the moisture-proof film 90, respectively. It is possible to prevent moisture permeation (moisture absorption) from occurring in the apparatus from these joint portions and the sealing material 52 itself, or intrusion of moisture.

  In the liquid crystal device (liquid crystal cell 150) of FIG. 3, the moisture-proof film 90 is continuously formed on each side of the substrates 10, 20, the conductive films 9, 21, the alignment films 40, 60, and the sealing material 52, as in FIG. And is arranged so as to cover the entire area. Further, unlike the liquid crystal cell 150 of FIG. 1, the side surface of the sealing material 52 is located inward compared to the side surfaces of the substrates 10 and 20, and the moisture-proof film 90 is continuously formed along the step. ing.

  That is, in the liquid crystal cell 150 of FIG. 3, the side surface of the sealing material 52 is recessed compared to the side surfaces of the substrates 10 and 20, and in addition to the side surfaces of the substrates 10 and 20, the conductive films 9 and 21, and the alignment films 40 and 60. The moisture-proof film 90 is filled in the recess. In terms of the film thickness of the moisture-proof film 90, the side surface position of the sealing material 52 is thicker than the side surface positions of the substrates 10 and 20, the conductive films 9 and 21, and the alignment films 40 and 60. Therefore, according to the liquid crystal cell 150 of this example, the portion covered with the thick moisture-proof film 90, that is, the interface (bonding portion) between the alignment films 40 and 60 and the sealing material 52 and the side surface of the sealing material 52. Further, moisture absorption (moisture permeability) and moisture intrusion are prevented more reliably. Further, in the liquid crystal cell 150 of this example, a step is formed on the side surfaces of the substrates 10 and 20, and the moisture-proof film 90 is formed so as to cover the step portion. Therefore, the moisture-proof film 90 is engaged with the step portion. In this state, it is formed on the side surfaces of the substrates 10 and 20, and therefore, the adhesion of the moisture-proof film 90 to the side surfaces of the substrates 10 and 20 becomes better.

  In the liquid crystal cell 140 of FIG. 4, the liquid crystal cell 150 of FIG. 3 has a moisture-proof film 90 that covers not only the entire side surfaces of the substrates 10 and 20 but only the alignment films 40 and 60 and the sealing material 52. It is formed with. Even in this case, since the moisture permeation preventing effect of the moisture proof film 90 is excellent, moisture absorption (moisture permeability) from the interface (bonding portion) between the alignment films 40 and 60 and the seal material 52 and from the side surface of the seal material 52 is achieved. Intrusion of moisture and water can be reliably prevented.

Next, a specific configuration example of the liquid crystal device of the present invention will be described.
FIG. 5 is a plan view showing the overall structure of the liquid crystal device of this embodiment. 6 is a longitudinal sectional view of the liquid crystal device of FIG. FIG. 7 is an equivalent circuit diagram showing switching elements, signal lines, and the like in a plurality of pixels arranged in a matrix constituting the image display region of the liquid crystal device of this embodiment.

  As shown in FIG. 5 and FIG. 6, in this liquid crystal device (transmission type liquid crystal cell 150), the TFT array substrate 10 and the counter substrate 20 are bonded together by a sealing material 52, and in a region partitioned by the sealing material 52. Liquid crystal 50 is enclosed and held. The sealing material 52 is formed with a liquid crystal injection port 55 for injecting liquid crystal after the TFT array substrate 10 and the counter substrate 20 are bonded together at the time of manufacturing. The liquid crystal injection port 55 is sealed after the liquid crystal injection. It is sealed with a material 54.

  A peripheral part (not shown) made of a light-shielding material is formed in a region inside the sealing material 52, while a data line driving circuit 201 and a mounting terminal 202 are provided in the TFT array substrate in a region outside the sealing material 52. The scanning line driving circuit 204 is formed along two sides adjacent to the one side. On the remaining side of the TFT array substrate 10, a plurality of wirings 205 are provided for connecting between the scanning line driving circuits 204 provided on both sides of the image display area.

  As shown in FIG. 7, a pixel electrode 9 and a TFT element 30 that is a switching element for controlling the pixel electrode 9 are formed on a plurality of pixels arranged in a matrix that forms an image display area. The data line 6 a to which the image signal is supplied is electrically connected to the source of the TFT element 30. The image signals S1, S2,..., Sn supplied to the data line 6a are supplied line-sequentially in this order, or are supplied for each group to a plurality of adjacent data lines 6a.

  In addition, the scanning line 3a is electrically connected to the gate of the TFT element 30, and scanning signals G1, G2,..., Gm are applied to the plurality of scanning lines 3a in a pulse-sequential manner at predetermined timing. The The pixel electrode 9 is electrically connected to the drain of the TFT element 30. By turning on the TFT element 30 for a certain period, the image signals S1, S2,. Sn is written at a predetermined timing.

A predetermined level of image signals S1, S2,..., Sn written to the liquid crystal via the pixel electrode 9 is held for a certain period with the common electrode described later. This liquid crystal modulates light by changing the orientation and order of the molecular assembly according to the applied voltage level, thereby enabling gradation display.
In order to prevent the held image signal from leaking, a storage capacitor 17 is added in parallel with the liquid crystal capacitor formed between the pixel electrode 9 and the common electrode.

  5 and 6, the pixel electrode 9 and an alignment film 40 for controlling the alignment of the liquid crystal molecules in the liquid crystal layer 50 when no voltage is applied are formed on the surface of the TFT array substrate 10 on the liquid crystal layer 50 side. Is formed. A polarizing plate that transmits only predetermined polarized light and, if necessary, a dustproof plate are disposed on the surface of the TFT array substrate 10 opposite to the liquid crystal layer 50 side.

  On the other hand, on the surface of the counter substrate 20 on the liquid crystal layer 50 side, a common electrode 21 made of a transparent electrode material such as ITO and an alignment film 60 for controlling the alignment of liquid crystal molecules in the liquid crystal layer 50 when no voltage is applied. And are formed. A polarizing plate that transmits only predetermined polarized light and, if necessary, a dustproof plate are disposed on the surface of the TFT array substrate 10 opposite to the liquid crystal layer 50 side.

  In the liquid crystal cell 150 of this example, the moisture-proof film 90 is formed so as to continuously and entirely cover the side surfaces (end surfaces) of the substrate 10, the conductive films 9 and 21, the alignment films 40 and 60, and the sealing material 52. It is arranged. Note that unnecessary portions of the moisture-proof film such as electrodes and wiring (data line driving circuit 201, mounting terminal 202, wiring 205, etc.) are formed after masking in advance, or the moisture-proof film is removed after film formation. Is exposed.

  As a result, in the liquid crystal cell 150 of this example, moisture absorption (moisture permeability) from the respective side surfaces of the conductive films 9 and 21, the alignment films 40 and 60, and the sealing material 52 is prevented by the moisture-proof film 90. 20 and the conductive film 9, 21, the conductive film 9, 21 and the alignment film 40, 60, and the alignment film 40, 60 and the sealing material 52, respectively. Therefore, moisture absorption and moisture intrusion into the inside of the apparatus from those joint portions (interfaces) are prevented.

  In the present embodiment, only the TN mode liquid crystal device has been described. However, the present invention is not limited to this, and the present invention does not apply voltage such as a vertical alignment mode and an STN (Super Twisted Nematic) mode. The alignment state of the liquid crystal molecules at the time can be applied to any liquid crystal device. When the present invention is applied to a vertical alignment mode liquid crystal device, the liquid crystal layer has a positive and negative dielectric anisotropy in which the major and minor axis directions of the liquid crystal molecules are more easily polarized than the minor and major axis directions. What is necessary is just to comprise. In this case, when no voltage is applied, the liquid crystal molecules in the liquid crystal layer are controlled by the alignment film and are aligned in a predetermined direction, whereas when a voltage is applied, the liquid crystal molecules in the liquid crystal layer have their major axis direction changed. Since it is arranged in a direction substantially perpendicular to the direction of the vertical electric field generated between the pair of substrates, the arrangement of liquid crystal molecules when no voltage is applied and when the voltage is applied can be optically identified and displayed. it can.

FIG. 8 is a perspective view showing the overall configuration of a passive matrix transmissive liquid crystal device.
This transmissive liquid crystal device is schematically configured to include a pair of substrates 70 and 80 arranged to face each other with a liquid crystal layer (not shown) interposed therebetween.

  More specifically, the substrate 70 includes a plurality of transparent electrodes 72 formed in a stripe shape on the surface of the substrate body 71 on the liquid crystal layer side, a protective film (not shown) and an alignment film containing ion-adsorbing fine particles. (Not shown) are sequentially provided. The substrate 80 includes a large number of transparent electrodes 82 formed in a stripe pattern on the surface of the substrate body 81 on the liquid crystal layer side, a protective film (not shown) containing ion-adsorbing fine particles, and an alignment film (not shown). ) In order.

As shown in the figure, the transparent electrode 72 of the substrate 70 and the transparent electrode 82 of the substrate 80 are formed in a direction crossing each other. Further, a moisture-proof film (not shown) is continuously formed on the entire sides of the pair of substrates 70 and 80.
As described above, the present invention can also be applied to a passive matrix transmissive liquid crystal device, and the same effect as that of an active matrix transmissive liquid crystal device can be obtained.

  In each of the above embodiments, only the active matrix type transmissive liquid crystal device and the passive matrix type transmissive liquid crystal device using TFT elements have been described. However, the present invention is not limited to these, and the TFD ( The present invention can also be applied to an active matrix liquid crystal device using a two-terminal element typified by a thin-film diode element.

  Further, in each of the embodiments described above, the transmissive liquid crystal device has been taken up and described, but the present invention only needs to have a configuration in which a moisture-proof film is formed on the outer surface of a pair of substrates after being bonded together. It is not limited to the above embodiments. For example, the present invention can be applied to a reflective liquid crystal device other than a transmissive liquid crystal device and a transflective liquid crystal device, and can be applied to a liquid crystal device having any structure.

(Electronics)
Next, a projector will be described as an example of the electronic apparatus of the invention.
FIG. 9 schematically shows the projector.
This projector PJ1 uses the liquid crystal device of the present invention as a light modulation means (liquid crystal light valve), and includes a transmissive liquid crystal light valve for each of different colors of R (red), G (green), and B (blue). 3 plate type intermittent display type color liquid crystal projector.

  As shown in FIG. 9, the projector PJ1 includes a light source 810, dichroic mirrors 813, 814, reflection mirrors 815, 816, 817, an incident lens 818, a relay lens 819, an exit lens 820, and a liquid crystal light valve 822. , 823, 824, a cross dichroic prism 825, and a projection lens 826.

The light source 810 includes a lamp 811 such as a metal halide and a reflector 812 that reflects the light of the lamp.
The dichroic mirror 813 transmits red light contained in white light from the light source 810 and reflects blue light and green light. The transmitted red light is reflected by the reflection mirror 817 and enters the red light liquid crystal light valve 822. The green light reflected by the dichroic mirror 813 is reflected by the dichroic mirror 814 and enters the liquid crystal light valve 822 for green light. Further, the blue light reflected by the dichroic mirror 813 passes through the dichroic mirror 814. For blue light, in order to prevent light loss due to a long optical path, a light guide means 821 including a relay lens system including an incident lens 818, a relay lens 819, and an exit lens 820 is provided. Blue light is incident on the blue light liquid crystal light valve 824 via the light guiding means 821.

  The three color lights modulated by the liquid crystal light valves 822, 823, and 824 are incident on the cross dichroic prism 825. The cross dichroic prism 825 is formed by bonding four right-angle prisms. A dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are formed in an X shape at the interface. Yes. These dielectric multilayer films combine the three color lights to form light representing a color image. The synthesized light is projected onto the screen 827 by the projection lens 826 which is a projection optical system, and the image is enlarged and displayed.

  According to such a projector PJ1, since the display quality is prevented from deteriorating due to moisture absorption (moisture permeability) and water intrusion in the liquid crystal light valves 822, 823, and 824, display quality is improved and display reliability is improved. Will be improved.

In this example, the liquid crystal device of the present invention is adopted for each of the liquid crystal light valves for red light, green light, and blue light. However, the liquid crystal device is not necessarily applied to all liquid crystal light valves. When applied to at least one of the liquid crystal light valves of R, G, and B, the effect can be obtained. The liquid crystal device of the present invention is particularly effective when applied to a liquid crystal light valve for blue light (B) having high light energy.
Further, although the description has been given by taking a three-plate projection display device (projector) as an example, the present invention can also be applied to a single-plate projection display device or a direct-view display device.

  The liquid crystal device of the present invention can also be applied to electronic devices other than projectors. As a specific example, a mobile phone including the liquid crystal device of the present invention in a display portion can be given. Other electronic devices include, for example, a video camera, a personal computer, a head mounted display, a fax machine with a display function, a digital camera finder, a portable TV, a PDA (Personal Digital Assistant), an electronic notebook, and an electric bulletin board. And advertising announcement displays.

  As described above, the preferred embodiments according to the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the examples. It is obvious for those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims. It is understood that it belongs to.

1 is a schematic cross-sectional view showing a liquid crystal cell as an example of a liquid crystal device of the present invention. FIG. 6 is a diagram showing a modification of the liquid crystal device in FIG. 1. FIG. 6 is a diagram showing a modification of the liquid crystal device in FIG. 1. FIG. 6 is a diagram showing a modification of the liquid crystal device in FIG. 1. The top view which shows the whole structure of a liquid crystal device. FIG. 6 is a longitudinal sectional view of the liquid crystal device of FIG. 5. FIG. 6 is an equivalent circuit diagram illustrating an image display area of the transmissive liquid crystal device. FIG. 6 is a perspective view illustrating a passive matrix transmissive liquid crystal device. FIG. 2 schematically shows an example of a projector.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Substrate, 20 ... Substrate, 9 ... Pixel electrode (conductive film), 21 ... Common electrode (conductive film), 50 ... Liquid crystal layer (liquid crystal), 52 ... Sealing material, 40, 60 ... Alignment film, 70 ... Lower side Substrate, 80 ... upper substrate, 90 ... moisture-proof film, 100, 140, 150 ... liquid crystal cell (liquid crystal device), 130 ... liquid crystal panel (liquid crystal device), PJ1 ... projector.

Claims (7)

A liquid crystal device having a liquid crystal sandwiched between a pair of substrates facing each other,
An alignment film is provided on each inner surface of the pair of substrates,
A sealing material is provided between the alignment films in a state where the liquid crystal is sealed,
A sol-gel solution containing a silane coupling material, a metal alkoxide, and water is applied and cured on the side end surfaces of the pair of substrates in a state of covering at least the sealing material and the alignment film. A liquid crystal device having a moisture-proof film formed thereon.   2. The liquid crystal device according to claim 1, wherein the metal alkoxide comprises at least one of Zr alkoxide, Al alkoxide, Ti alkoxide, and Mg alkoxide.   3. The liquid crystal device according to claim 1, wherein the silane coupling material includes a plurality of types of alkoxysilanes, and the alkoxysilanes have different numbers of carbon atoms in the respective alkoxy groups.   The sol-gel solution contains a water-repellent material having a water-repellent group, and the moisture-proof film obtained by curing the sol-gel solution has water repellency. 4. The liquid crystal device according to any one of 3.   5. The liquid crystal device according to claim 4, wherein the moisture-proof film is formed on the entire surface on the side end face side of the pair of substrates. A step of bonding a pair of substrates having an alignment film formed on the inner surface through a sealing material;
Disposing a liquid crystal in a region surrounded by the sealing material;
Applying a sol-gel solution containing a silane coupling material, a metal alkoxide, and water in a state of covering at least the sealing material and the alignment film on the side end face sides of the pair of substrates;
And a step of curing the sol-gel solution to form a moisture-proof film. An electronic apparatus comprising the liquid crystal device according to any one of claims 1 to 5.

Images